Protective wear sleeve for cutting element

ABSTRACT

A protective wear sleeve for a cutting tool assembly that includes a solid body that has a shaft portion, a radial collar portion, and a central bore that defines a central axis. The shaft has a forward end and a rearward end, wherein the radial collar is integral with the forward end. The radial collar has a ring support surface that faces at least partially in an outward radial direction. The forward end of the shaft and the radial collar together define a tooth support surface that faces in a forward direction and has an outer diameter. At least one wear ring is disposed on the ring support surface and extends around the radial collar. The at least one wear ring has a hardness greater than that of the radial collar and has an outer diameter greater than that of the outer diameter of the tooth support surface.

This application is being filed on 13 Oct. 2015, as a PCT Internationalpatent application, and claims priority to U.S. Provisional PatentApplication No. 62/065,400, filed Oct. 17, 2014, the disclosure of whichis hereby incorporated by reference herein in its entirety.

TECHNICAL FIELD

The present disclosure relates generally to a replaceable apparatus,specifically a protective wear sleeve, for mounting reducing elementsused by excavation machines such as surface excavation machines.

BACKGROUND

Relatively hard materials are often processed for mining andconstruction. The variety of materials include rock, concrete, asphalt,coal, and a variety of other types of mineral-based materials. A numberof different methods for reducing the size of these hard materials havebeen developed. One method has been the use of reducing machines havingrotary reducing components that move rigid and specialized reducingelements through paths of travel. The reducing components can includerotating drums that move the reducing elements through circular paths oftravel. Such drums are typically attached to corresponding machines witha mechanism that allows the position and orientation of the drum to becontrolled, to bring the reducing elements into contact with thematerial being reduced. Alternative reducing components can includeboom-mounted chains that carry reducing elements. The chains aretypically driven/rotated about their corresponding booms. The reducingelements are mounted to and move along the paths of travel defined bythe chains. In use, the booms are moved (e. g., through a pivotingmotion) to positions where the reducing elements are brought intocontact with the material being reduced.

The reducing elements of reducing machines have been developed towithstand the impact loads and abrasion associated with materialreduction activities. Reducing elements can be constructed in a varietyof shapes and sizes and have been labeled with various terms includingcutters, chisels, picks, teeth, etc. Typical reducing elements includeleading impact points or edges and bases. The reducing element holders,or tool holders, are constructed to fit into mounting structures thatare integrated with drums or chains used to carry the reducing elementsduring material reducing applications. The harsh environment associatedwith material reducing applications virtually guarantees that thereducing elements will wear down over time.

Often, the tips or edges of the reducing elements have a harderconstruction (e.g., a solid carbide construction) than the tool holdersof the reducing elements. When using new reducing elements to reducematerial, the leading points or edges are exposed to the majority of theimpacts and abrasion action. However, once the leading tips or edgesbecome worn, the tool holders and other components are exposed to moreimpacts and abrasive action. A variety of potential problems can arisewhen this occurs, including that the tool holders are less efficient atbreaking the material, causing inefficient operation. Once reducingelements are worn there is also a risk of causing damage to the mountingstructures of the drums or chains.

A protective wear sleeve can be used as an intermediate wear partbetween the reducing element and the base. However, the most common usefor these sleeves has been to reduce wear on the holder from thespinning reducing element, which tends to, over time, bore out the areathat the tooth is mated next to, as described in U.S. Pat. No.8,783,785, U.S. Pat. No. 8,657,385, and U.S. Pat. No. 5,088,797.However, due to the harsh environment the protective wear sleeve issubjected to, the wear sleeve often also wears at a rapid rate on theexterior, thereby forcing replacement.

SUMMARY

In accordance with the following disclosure, the above and other issuesare addressed by the following.

The downtime associated with replacing wear components on a cutting drumcan be extensive for the machine that the drum is mounted to. Suchdowntime makes the machine less efficient, which leads to a higheroperating cost. At the same time, if too much time is allowed to passbefore replacement of wear components, other, more costly, componentscan be damaged, for example tool holders or the drum itself. Thereplacement of worn tool holders can be costly and difficult such thatthe tool holders are often significantly worn before they are replaced.As a result of these issues, there can be significant benefits toreplacing the other wear components before wear has progressed past anunacceptable point. A protective wear sleeve provides an option as anintermediate wear part, protecting the more expensive components fromrapid wear. Therefore, there is an ongoing need for a protective wearsleeve that has an extended life. An extended lifetime translates intoless downtime and a lower replacement frequency. In particular, there isa need for a protective wear sleeve having wear protection on the outerexposed portion of the sleeve that is not protected by the reducingelement.

According to an example aspect, the disclosure is directed to aprotective wear sleeve for a tooth holder of a cutting tool assemblywherein the tooth holder contains a central bore. The protective wearsleeve includes an elongate body made from a base material, the elongatebody including a tooth bore that defines a tooth axis, an axial forwardend and an axial rearward end, a mount portion at the rearward endconfigured for an interference press-fit with the central bore of thetooth holder. The elongate body further including a tooth support collarat the forward end, the tooth support collar including a tooth supportsurface projecting from the tooth bore out to a tooth collar diameter.The tooth support surface facing generally in a forward direction. Thetooth support collar further including a shoulder with an outer diameterequal to, or greater than, the tooth collar diameter and a shoulderthickness along the elongate axis of the body, wherein the shoulderincludes a hardfacing portion.

According to another aspect, the disclosure is directed to a protectivewear sleeve for a cutting tool assembly that includes a solid bodyhaving a first portion and a second portion, the body having a centralbore where the central bore defines a central axis. The first portion ofthe solid body is a shaft portion having a forward end and a rearwardend, and the second portion of the solid body is a radial collarintegral with the forward end of the shaft portion. The radial collarhas a ring support surface that faces at least partially in an outwardradial direction. The forward end of the shaft portion and the radialcollar together define a tooth support surface that faces in a forwarddirection, the tooth support surface having an outer diameter. At leastone wear ring is disposed on the ring support surface, the at least onewear ring extending around the radial collar. The at least one wear ringhas a hardness greater than that of the radial collar and has an outerdiameter greater than that of the outer diameter of the tooth supportsurface.

According to another aspect, the disclosure is directed to an apparatusincluding a holding block having a protective wear sleeve opening, acutting tooth having a support flange and a shank, and a protective wearsleeve. The protective wear sleeve includes a solid body having a firstportion and a second portion, the body having a central bore forreceiving the shank of the cutting tooth, the central bore defining acentral axis. The first portion is a shaft portion having a forward endand a rearward end, and the second portion is a radial collar integralwith the forward end of the shaft portion. The radial collar has a ringsupport surface that faces at least partially in an outward radialdirection. The forward end of the shaft portion and the radial collartogether define a tooth support surface that faces in a forwarddirection, the tooth support being configured to encase a back side ofthe support flange of the cutting tooth. The protective wear sleevefurther includes at least one wear ring disposed on the ring supportsurface, the at least one wear ring extending around the radial collar,the at least one wear ring having a hardness greater than that of theradial collar and having an outer diameter greater than that of an outerdiameter of the tooth support flange. Wherein the protective wear sleeveis press fit into the protective wear sleeve opening of the holdingblock, and the cutting tooth being secured in the central bore of theprotective wear sleeve and being rotatable around the central axis ofprotective wear sleeve.

A variety of additional aspects will be set forth in the descriptionthat follows. These aspects can relate to individual features and tocombinations of features. It is to be understood that both the foregoinggeneral description and the following detailed description are exemplaryand explanatory only and are not restrictive of the broad concepts uponwhich the embodiments disclosed herein are based.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a front view of a portion of a surface excavationmachine showing a drum with reducing elements, in accordance with theprinciples of the present disclosure;

FIG. 2 illustrates a perspective view of a cutting apparatus that can bemounted to the drum shown in FIG. 1;

FIG. 3 illustrates a front perspective view of the cutting apparatusshown in FIG. 2;

FIG. 4 illustrates a cross-sectional view of the cutting apparatus ofFIG. 3 taken along line A;

FIG. 5 illustrates a perspective exploded view of the cutting apparatusshown in FIG. 2;

FIG. 6 illustrates a perspective view of a protective wear sleeveaccording to one embodiment of the present disclosure;

FIG. 7 illustrates a front view of the protective wear sleeve shown inFIG. 6;

FIG. 8 illustrates a cross-sectional view of the protective wear sleeveof FIG. 7 taken along line A;

FIG. 9 illustrates a side perspective view of the protective wear sleeveshown in FIG. 6;

FIG. 10 illustrates a perspective view of a protective wear sleeveaccording to one embodiment of the present disclosure;

FIG. 11 illustrates a front view of the protective wear sleeve shown inFIG. 10;

FIG. 12 illustrates a cross-sectional view of the protective wear sleeveof FIG. 11 taken along line A.

DETAILED DESCRIPTION

The present application discloses a protective wear sleeve. Because wearsleeves can be subjected to wear when a cutting action is being carriedout, it is advantageous to increase the lifetime of the wear sleeve. Thesleeve disclosed herein is configured to resist wear on exteriorportions of the sleeve, specifically the radial collar.

FIG. 1 depicts a cutting drum 38 attached to a surface excavationmachine 36. The cutting drum 38 being designed to, once rotated, reducematerial by way of a plurality of cutting apparatuses 40 mounted to thesurface of the drum 38. The cutting apparatuses 40 can be arranged in avariety of patterns for a variety of different applications. Eachcutting apparatus 40 can include a reducing element 46, or tooth, a toolholder 42 and a protective wear sleeve 10.

FIGS. 2-3 depict the cutting apparatus 40. The assembled cuttingapparatus 40 can include the reducing element 46, the protective wearsleeve 10, and the tool holder 42. In some embodiments, the tool holder42 may be secured to a base 44 for securing to a cutting drum. Further,the protective wear sleeve 10 can include a wear ring 22. The wear ring22 can be configured to provide a high wear resistance. In someembodiments, the tool holder 42 may be one piece or include multiplepieces and other wear components.

FIG. 4 depicts a cross-sectional view along line A in FIG. 3. FIG. 5depicts an exploded view of the cutting apparatus 40. As shown, the toolholder 42 has a wear sleeve opening 54 configured to receive theprotective wear sleeve 10. The wear sleeve 10 has a central bore 12configured to receive the tooth 46. The tooth 46 can be secured to thetool holder 42 by way of a fastener 52, such as a pin or clip. The tooth46 can include a shank 50 and a support flange 48. The protective wearsleeve 10 can be press fit into the wear sleeve opening 54 so as toprevent rotation of the protective wear sleeve 10 relative the toolholder 42. Also, in some embodiments, the protective wear sleeve 10 canbe configured so that it may be orientated in any rotational orientationwithin the wear sleeve opening 54, with respect to the tool holder 42.This allows for rapid installation with a lower chance of installationerror. Additionally, the tooth 46 may be secured within the central bore12 of the protective wear sleeve 10. The tooth 46 can be secured withinthe protective wear sleeve 10 to allow for rotation of the tooth 46.When secured in the protective wear sleeve 10, the tooth support flange48 rests on a tooth support surface 20 of the protective wear sleeve 10.The wear ring 22 is configured to have a larger diameter than the toothsupport surface 20. This is advantageous because during a miningoperation, material will pass over the support flange of the tooth 46and contact the protective wear sleeve 10. Because of this repeatedcontact, the material that is outside of the diameter of the toothsupport flange is subjected to repeated abuse and tends to wear quickly.The wear ring 22 placed in this location is designed to slow wear to theprotective wear sleeve 10 so as to extend the life of the wear sleeve,extending replacement intervals.

FIG. 6 shows a perspective view of the protective wear sleeve 10. Theprotective wear sleeve 10 can include a shaft portion 14 and a radialcollar 16. The protective wear sleeve 10 also includes the central bore12 that travels through the center of the protective wear sleeve 10 anddefines a central axis 13. In some embodiments, the radial collar 16 canhave an axial thickness C running parallel to the central axis 13 andalso a radial thickness B so to have an outer diameter greater than thatof the shaft portion 14. In other embodiments, the radial thickness B ofthe radial collar 16 can be tapered, where the portion of the radialcollar 16 has a smaller thickness (i.e. smaller outer diameter) near theareas closer to the tooth support surface 20. The protective wear sleeve10 having a forward end 17, generally being the radial collar 16, and arearward portion 15, generally being the shaft portion 14. In thedepicted embodiment, together with the shaft portion 14, the radialcollar 16 can form the tooth support surface 20, the tooth supportsurface 20 being at the forward end 17 of the protective wear sleeve 10.The tooth support surface 20 can take on a variety of different shapebut always faces in a forward direction. While the tooth support surface20 is depicted as a planar surface, the surface can also be conical or avariety of other shapes while remaining generally forward facing. Insome embodiments, the tooth support surface can be configured to begenerally perpendicular to the central axis 13.

The protective wear sleeve 10 can also include the wear ring 22. Thewear ring 22 can be disposed around the radial collar 16. As depicted,the wear ring 22 can be disposed 360 degrees around the radial collar16. The wear ring 22 can be of a variety of materials. In someembodiments, the wear ring 22 can be a weld of hardfacing material. Insome embodiments, the wear ring 22 can be a weld of hardfacing materialthat is disposed 360 degrees around the radial collar 16. In such anembodiment, the protective wear sleeve 10 can be configured to beinserted at any angular rotation about the central axis 13 and stillprovide hardfacing protection relative to the direction of rotationaltravel of the tooth 46 held by the protective wear sleeve 10. Ahardfacing material can be a material that results from a process wherea harder material is applied to a less hard material, the less hardmaterial often called a base. Such a material can then be welded to thebase material. In other embodiments, the wear ring 22 may comprise amaterial with a hardness greater than that of the radial collar 16. Inother embodiments yet, the wear ring 22 may be comprised of a materialwith a hardness between about 40 HRC and about 70 HRC.

FIG. 7 depicts a front view of the protective wear sleeve of FIG. 5. Thewear ring 22 is shown to have an outer diameter greater than the outerdiameter of the tooth support surface 20. This configuration allowsadequate wear protection for portions of the protective wear sleeve 10that lie outside the diameter of the tooth support surface 20, suchportions being more prone to wear.

FIG. 8 shows a cross-sectional view along the section line A of FIG. 7.As shown, a portion of the shaft portion 14 is a unitary portion ofradial collar 16, whereby, together, both portions behave as one piece.The tooth support surface 20 can include a portion 21 defined by theshaft portion 14 and a portion 23 defined by the radial collar 16. Inthe depicted embodiment the central bore 12 is shown to be stepped. Inother embodiments, the central bore 12 may have a uniform diameter. Alsoshown in FIG. 8, the radial collar 16 can include a ring support surface18, being configured to hold the wear ring 22. The ring support surface18 can have a scalloped shape, or groove-like structure. In someembodiments, the ring support surface 18 can face at least partially inan outward radial direction. In other embodiments, the ring supportsurface 18 can face at least partially in an outward radial directionand at least partially in a forward axial direction. Alternatively, insome embodiments, the ring support surface 18 may include an about90-degree angled shoulder. In other embodiments still, the ring supportsurface 18 may be machined. Additionally, the ring support surface 18may be on the radial collar 16 near the tooth support surface 20. Inother embodiments, the ring support surface 18 may be located at anylocation along the radial collar 16 and have a maximum axial thicknessequal to the axial thickness of the radial collar 16. FIG. 9 depicts theprotective wear sleeve 10 without a wear ring.

In some embodiments the interior surface of central bore 12 can be havea first hardness, the tooth support surface 20 can have a secondhardness, the radial collar 16 can have a third hardness, and the wearring 22 can have a fourth hardness. In some embodiments, the interiorsurface of the central bore 12 and the tooth support surface 20 may haveequal hardnesses. In other embodiments, the interior surface and thecentral bore 12 may be induction hardened. Induction hardening takesplaces when a metal part is heated by induction and then quenched. Theprocess changes the material properties of the metal part, therebyincreasing its hardness and brittleness. In still other embodiments, thewear ring 22 can have a hardness greater than that of the radial collar16, and less than that of the tooth support surface 20 and interiorsurface of the central bore 12. In still other embodiments, the wearring 22 can have a hardness greater than that of the radial collar 16,the tooth support surface 20 and interior surface of the central bore12. In the same embodiment, the radial collar 16 may have a hardnessless than that of the tooth support surface 20 and the interior surfaceof the central bore 12. In some embodiments, the radial collar 16 canhave a hardness between about 20 HRC and about 30 HRC. In otherembodiments, the tooth support surface 20 and the inner surface of thecentral bore 12 can have a hardness between about 50 HRC and about 60HRC. In other embodiments still, the radial collar 16 and the shaftportion 14 can be of 4140 steel.

In some embodiments the shaft 14 can have a length between about 3inches and about 4 inches. In some embodiments, the central bore 12 mayhave an outer diameter between about 1.70 inches and about 1.75 inches.In other embodiments, the tooth support surface 120 can have an outerdiameter between about 3 inches and about 4.75 inches. In otherembodiments still, the wear ring 22 can have an outer diameter betweenabout 3 inches and about 4.75 inches. In other embodiments, the shaftportion 14 can have an outer diameter between about 2.250 inches andabout 2.260 inches.

FIG. 10 depicts a protective wear sleeve 110 according to one embodimentof the present disclosure. The protective wear sleeve 110 of FIG. 10 issimilar to that of the protective wear sleeve 10 of FIG. 7. Similarly,the protective wear sleeve 110 includes a shaft portion 114, a radialcollar portion 116, a central bore 112, a central axis 113, a forwardportion 117, a rearward portion 115, a ring support surface 118, a toothsupport surface 120, and a wear ring 122 a, 122 b. In FIG. 10 theprotective wear sleeve 110 includes a wear ring that includes twoindividual wear rings 122 a and 122 b. In other embodiments, a pluralityof wear rings may be disposed around the radial collar 116 of varyingthicknesses and diameters. In the depicted embodiment, the first wearring 122 a has a smaller outer diameter than the second wear ring 122 band is positioned closer to the tooth support surface 120, or forwardend of the protective wear sleeve 110. In other embodiments, theplurality of wear rings can have the same outer diameter. The wear rings122 a, 122 b can be of a variety of materials. In some embodiments, thewear rings 122 a, 122 b can be welds of hardfacing material. In otherembodiments, the wear rings 122 a, 122 b may comprise a material with ahardness greater than that of the radial collar 116. In otherembodiments yet, the wear rings 122 a, 122 b may be comprised of amaterial with a hardness between about 40 HRC and about 70 HRC. In stillother embodiments, the wear rings 122 a, 122 b may have differinghardnesses, each between about 40 HRC and about 70 HRC.

FIG. 11 depicts a front view of the protective wear sleeve of FIG. 10.The wear rings 122 a, 122 b are shown to have outer diameters greaterthan the outer diameter of the tooth support surface 120. Additionally,as shown, the wear ring 122 a has a larger outer diameter than the wearring 122 b. This orientation allows for adequate wear protection forportions of the protective wear sleeve 110 that lie outside the diameterof the tooth support surface 120, such portions being more prone towear.

FIG. 12 shows a cross-sectional view of the protective wear sleeve 110along the section line A of FIG. 11. Similar to the protective wearsleeve 10 above, a portion of the shaft portion 114 is a unitary portionof radial collar 116, whereby, together, both portions behave as onepiece. The tooth support surface 120 can include a portion 121 definedby the shaft portion 114 and a portion 123 defined by the radial collar116. Also, the radial collar 116 can have a radial thickness D and anaxial thickness E. As shown in FIG. 11, the radial collar 116 caninclude a plurality of ring support surfaces 118 a, 118 b, the supportsurfaces 118 a, 118 b being configured to hold a plurality of wearrings. While the depicted embodiment shows two ring support surfaces 118a, 188 b, it is appreciated that more than two ring support surfaces maybe positioned on the radial collar 116. In some embodiments, each ringsupport surface 118 a, 118 b may hold a singular wear ring. In otherembodiments, each ring support surface 118 a, 118 b may hold a pluralityof wear rings. The ring support surfaces 118 a, 118 b can have ascalloped shape or groove-like structure. In some embodiments, the ringsupport surfaces 118 a, 118 b can face at least partially in an outwardradial direction. In other embodiments, the ring support surfaces 118 a,118 b can face at least partially in an outward radial direction and atleast partially in an axial direction. Alternatively, in someembodiments, the ring support surfaces 118 a, 118 b may be oriented inan identical direction or different directions. In some embodiments, atleast one ring support surface 118 a, 118 b may include an about90-degree angled shoulder. In other embodiments still, the ring supportsurfaces 118 a, 118 b may be machined. Additionally, the ring supportsurfaces 118 a, 118 b may be oriented on the radial collar 116 near thetooth support surface 120. In other embodiments, the ring supportsurfaces 118 a, 118 b may be located at any location along the radialcollar 116 and have a maximum combined axial thickness about equal tothe axial thickness of the radial collar 116.

In some embodiments the interior surface of central bore 112 can be havea first hardness, the tooth support surface 120 can have a secondhardness, the radial collar 116 can have a third hardness and the wearrings 122 a, 122 b can have a fourth hardness. In some embodiments, thewear rings 122 a, 122 b can have different hardnesses. In otherembodiments still, the forward wear ring 122 a can have a greaterhardness than any trailing wear ring 122 b. In other embodiments, theforward wear ring 122 a can have a hardness less than any trailing wearring 122 b. In some embodiments, the interior surface of the centralbore 112 and the tooth support surface 120 may have equal hardnesses. Inother embodiments, the interior surface of the central bore 112 and thetooth support surface 120 may be induction hardened. In still otherembodiments the wear rings 122 a, 122 b can have hardnesses greater thanthat of the radial collar 116, the tooth surface 120 and interiorsurface of the central bore 112. In still other embodiments, the wearrings 122 a, 122 b can have hardnesses greater than that of the radialcollar 116, and less than that of the tooth support surface 120 andinterior surface of the central bore 112. In the same embodiment, theradial collar 116 may have a hardness less than that of the toothsupport surface 120 and the interior surface of the central bore 112. Insome embodiments, the radial collar 116 can have a hardness betweenabout 20 HRC and about 30 HRC. In other embodiments, the tooth supportsurface 120 and the inner surface of the central bore 112 can have ahardness between about 50 HRC and about 60 HRC. In other embodimentsstill, the radial collar 116 and the shaft portion 114 can be of 4140steel.

In some embodiments the shaft 114 can have a length between about 3inches and about 4 inches. In some embodiments, the central bore 112 mayhave an outer diameter between about 1.70 inches and about 1.75 inches.In other embodiments, the tooth support surface 120 can have a diameterbetween about 3 inches and about 4.5 inches. In other embodiments still,the wear ring 122 can have an outer diameter of about between about 3inches and about 4.5 inches. In other embodiments, the shaft portion 114can have an outer diameter between about 2.250 inches and about 2.260inches.

The above specification, examples and data provide a completedescription of the manufacture and use of the composition of theinventive aspects. Since many embodiments of the disclosure can be madewithout departing from the spirit and scope of the inventive aspects,the inventive aspects reside in the claims hereinafter appended.

What is claimed is:
 1. A protective wear sleeve for a tooth holder of acutting tool assembly wherein the tooth holder contains a central bore,the protective wear sleeve comprising: an elongate body made from a basematerial, the elongate body including: a tooth bore that defines a toothaxis; an axial forward end and an axial rearward end; a mount portion atthe rearward end configured for an interference press-fit with thecentral bore of the tooth holder; and a tooth support collar at theforward end, the tooth support collar including: a tooth support surfaceprojecting from the tooth bore out to a tooth collar diameter, the toothsupport surface facing generally in a forward direction; and a shoulderwith an outer diameter equal to, or greater than, the tooth collardiameter and a shoulder thickness along the elongate axis of the body,wherein the shoulder includes a hardfacing portion.
 2. The protectivewear sleeve of claim 1, wherein the base material is a medium carbonsteel induction hardened.
 3. The protective wear sleeve of claim 1,wherein the shoulder includes a groove that is configured to hold thehardfacing portion so that the hardfacing portion has an outer diameterequal to, or greater than, the outer diameter of the shoulder.
 4. Theprotective wear sleeve of claim 1, wherein the hardfacing portion iscomprised of a plurality of beads of hardfacing material formed on theshoulder.
 5. The protective wear sleeve of claim 1 wherein thehardfacing portion extends around the entire perimeter of the shoulder.6. A protective wear sleeve for a cutting tool assembly comprising: asolid body having a first portion and a second portion, the body havinga central bore, the central bore defining a central axis; the firstportion being a shaft portion having a forward end and a rearward end;the second portion being a radial collar integral with the forward endof the shaft portion, the radial collar having a ring support surfacethat faces at least partially in an outward radial direction; theforward end of the shaft portion and the radial collar together defininga tooth support surface that faces generally in a forward direction, thetooth support surface having an outer diameter; and at least one wearring disposed on the ring support surface, the least one wear ringextending around the radial collar, the at least one wear ring having ahardness greater than that of the radial collar and having an outerdiameter greater than that of the outer diameter of the tooth supportsurface.
 7. The protective wear sleeve of claim 6, wherein the boreincludes an inner bore surface and wherein the inner bore surface andthe tooth support surface are induction hardened.
 8. The protective wearsleeve of claim 7, wherein the at least one wear ring has a hardnessgreater than the hardness of the inner bore surface and tooth supportsurface.
 9. The protective wear sleeve of claim 6, wherein the innerbore surface and the tooth support surface have a first hardness and theradial collar has a second hardness and wherein the first hardness isgreater than the second hardness.
 10. The protective wear sleeve ofclaim 9, wherein the at least one wear ring has a third hardness, andwherein the third hardness is greater than the first hardness.
 11. Theprotective wear sleeve of claim 6, wherein the ring support surfaceincludes a groove that is configured to hold the at least one wear ring.12. The protective wear sleeve of claim 6, wherein the at least one wearring has a hardness of about 40 HRC to about 70 HRC.
 13. The protectivewear sleeve of claim 6, wherein the at least one wear ring has ahardness of about 45 HRC to about 70 HRC.
 14. The protective wear sleeveof claim 6, wherein the at least one wear ring has a hardness of about50 HRC to about 70 HRC.
 15. The protective wear sleeve of claim 6,wherein the at least one wear ring has a hardness of about 60 HRC toabout 70 HRC.
 16. The protective wear sleeve of claim 6, wherein the atleast one wear ring includes first and second wear rings.
 17. Theprotective wear sleeve of claim 16, wherein the first wear ring has anoutermost diameter smaller than an outermost diameter of the second wearring and wherein the first wear ring is positioned in front of thesecond wear ring relative to the forward direction.
 18. The protectivewear sleeve of claim 17, wherein the ring support surface includes firstand second grooves configured to hold first and second wear rings. 19.The protective wear sleeve of claim 6, wherein the ring support surfacefaces at least partially in an outward radial direction and at leastpartially in an axial direction.
 20. The protective wear sleeve of claim6 wherein the wherein the shaft portion has an outer diameter betweenabout 2.250 inches and about 2.260 inches and the central bore has adiameter between about 1.70 inches and about 1.75 inches.
 21. Anapparatus comprising: a holding block having a protective wear sleeveopening; a cutting tooth having a support flange and a shank; and aprotective wear sleeve including: a solid body having a first portionand a second portion, the body having a central bore for receiving theshank of the cutting tooth, the central bore defining a central axis;the first portion being a shaft portion having a forward end and arearward end; the second portion being a radial collar integral with theforward end of the shaft portion, the radial collar having a ringsupport surface that faces at least partially in an outward radialdirection; the forward end of the shaft portion and the radial collartogether define a tooth support surface that faces in a forwarddirection, the tooth support surface being configured to encase a backside of the support flange of the cutting tooth; and at least one wearring disposed on the ring support surface, the at least one wear ringextending around the radial collar, the at least one wear ring having ahardness greater than that of the radial collar and having an outerdiameter greater than that of an outer diameter of the tooth supportflange; and wherein the protective wear sleeve is press fit into theprotective wear sleeve opening of the holding block, and the cuttingtooth being secured in the central bore of the protective wear sleeveand being rotatable around the central axis of protective wear sleeve.22. The apparatus of claim 21, wherein the holding block is secured toan outer surface of a rotatable cutting drum.